Minjae Kim

Mr. Minjae Kim

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 January 2023 in Polymers
Verified
Journal Article
Open access
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JNJaehyun Noh
Jaehyun Noh
MJMinho Jo
Minho Jo
HJHojin Jeon
Hojin Jeon
MKMinjae Kim
Minjae Kim
Jeongdai JoJeongdai Jo
Jeongdai Jo
Changwoo LeeChangwoo Lee
Changwoo Lee
The roll-to-roll manufacturing system is extensively used for mass producing products made of plastic, paper, and fabric in several traditional industries. When flexible substrates, also known as webs, are heated and transported inside the dryer, an inconsistent temperature distribution occurs on the material in the machine direction (MD) and cross-machine direction (CMD). If rollers are not aligned in parallel on the same plane in the roll-to-roll web handling process, or if roller misalignment exists, strain deviation occurs in the web, resulting in lateral displacement and web wrinkles. Therefore, this study examined a wrinkle, which is a thermal deformation that occurs when an inconsistent web temperature distribution is formed on the material inside a dryer. The changes in the elastic modulus and thermal expansion of the web were also examined. Experiments were conducted using a PET film, and its elastic modulus and thermal expansion were examined. The results showed that the presence of a web wrinkle defect can cause a thickness deviation in the functional layer manufactured on the web. Moreover, an appropriate operating speed should be set to reduce the CMD temperature deviation, thereby reducing instances of wrinkle defects.

19 March 2024 in Polymers
Verified
Journal Article
Open access
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MKMinjae Kim
Minjae Kim
MJMinho Jo
Minho Jo
JNJaehyun Noh
Jaehyun Noh
SLSangbin Lee
Sangbin Lee
JYJunyoung Yun
Junyoung Yun
Changwoo LeeChangwoo Lee
Changwoo Lee
In fabricating functional layers, including thin-film transistors and conductive electrodes, using roll-to-roll (R2R) processing on polymer-based PET film, the instability of the slot-die coating meniscus under a high-speed web impedes functional layer formation with the desired thickness and width. The thickness profiles of the functional layers significantly impact the performance of the final products. In this study, we introduce an electrohydrodynamic (EHD)-based voltage application module to a slot-die coater to ensure the uniformity of the cross-machine direction (CMD) thickness profile within the functional layer and enable a stable, high-speed R2R process. The module can effectively control the spreadability of the meniscus by utilizing variations in the surface tension of the ink. The effectiveness of the EHD module was experimentally verified by applying a high voltage to a slot-die coater while keeping other process variables constant. As the applied voltage increases, the CMD thickness deviation reduces by 64.5%, and the production rate significantly increases (up to 300%), owing to the formation of a stable coated layer. The introduction of the EHD-based application module to the slot-die coater effectively controlled the spreadability of the meniscus, producing large-area functional layers.

21 April 2025 in Surfaces and Interfaces
Verified
Journal Article
Open access
MKMinjae Kim
Minjae Kim
JNJaehyun Noh
Jaehyun Noh
YLYoonjae Lee
Yoonjae Lee
GCGyoujin Cho
Gyoujin Cho
Changwoo LeeChangwoo Lee
Changwoo Lee

29 January 2026 in Mathematics
Verified
Journal Article
Open access
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MKMinjae Kim
Minjae Kim
SLSangyoon Lee
Sangyoon Lee
DODongkeun Oh
Dongkeun Oh
BPByungho Park
Byungho Park
Jeongdai JoJeongdai Jo
Jeongdai Jo
Changwoo LeeChangwoo Lee
Changwoo Lee
In autonomous manufacturing systems, the performance of time-series-based anomaly detection and fault diagnosis is highly sensitive to window size selection. Conventional approaches rely on empirical rules or fixed window settings, which often fail to capture the diverse temporal characteristics of anomalies and lead to performance degradation. This study systematically addresses the window size selection problem by categorizing anomaly patterns into three representative types: variability, cycle, and local spike. Each pattern is associated with a distinct temporal scale and underlying physical mechanism. Based on this insight, an Anomaly Deviation-Based Window Size Selection (ADW) method is proposed, which quantitatively evaluates anomaly deviation as a function of window size. Unlike traditional preprocessing-oriented approaches, the proposed method redefines window size as a core design variable that directly governs anomaly representation and diagnostic sensitivity. The effectiveness of the ADW method is validated using tension data from a roll-to-roll continuous manufacturing process and vibration data from a rotating bearing fault dataset. Experimental results demonstrate that the proposed approach consistently identifies optimized window sizes tailored to different anomaly types, leading to improved fault classification accuracy and diagnostic robustness. The proposed framework provides a physically interpretable and data-driven guideline for adaptive window size selection in long-term autonomous manufacturing systems.